L. casei strain F0822 used in this study was isolated from a human faecal sample by spreading the faecal material onto LAMVAB agar plates, and identified to the species level by partially
sequencing the 16S rDNA gene. The culture was maintained by
subculture in MRS broth (Oxoid Ltd., Basingstoke, Hampshire, UK)
supplemented with 0.05% (w/v) L-cysteine using a 1% inoculum and
18 h of anaerobic incubation at 37 C. The culture was serially
transferred three times in the MRSC broth before experimental use.
Unless otherwise indicated, all reagents and materials used in this
work were obtained from SigmaeAldrich (St. Louis, MO, USA).